{"cve":"CVE-2026-40198","nvd":{"published":"2026-04-10T22:16:21.463","modified":"2026-10-26T21:10:00.170","status":"Analyzed","description":"Net::CIDR::Lite versions before 0.23 for Perl does not validate IPv6 group count, which may allow IP ACL bypass.\n\n_pack_ipv6() does not check that uncompressed IPv6 addresses (without ::) have exactly 8 hex groups. Inputs like \"abcd\", \"1:2:3\", or \"1:2:3:4:5:6:7\" are accepted and produce packed values of wrong length (3, 7, or 15 bytes instead of 17).\n\nThe packed values are used internally for mask and comparison operations. find() and bin_find() use Perl string comparison (lt/gt) on these values, and comparing strings of different lengths gives wrong results. This can cause find() to incorrectly report an address as inside or outside a range.\n\nExample:\n\n  my $cidr = Net::CIDR::Lite->new(\"::/8\");\n  $cidr->find(\"1:2:3\");  # invalid input, incorrectly returns true\n\nThis is the same class of input validation issue as CVE-2021-47154 (IPv4 leading zeros) previously fixed in this module.\n\nSee also CVE-2026-40199, a related issue in the same function affecting IPv4 mapped IPv6 addresses.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","score":7.5},"cwes":["CWE-1286"],"references":["https://github.com/stigtsp/Net-CIDR-Lite/commit/25d65f85dbe4885959a10471725ec9d250a589c3.patch","https://metacpan.org/release/STIGTSP/Net-CIDR-Lite-0.23/changes","https://www.cve.org/CVERecord?id=CVE-2026-40199"],"products":["stigtsp:net\\"],"source":"nvd","synced_at":"2026-10-26T21:38:48.864438205+00:00"},"epss":{"cve":"CVE-2026-40198","score":0.00309,"percentile":0.23543,"date":"2026-10-26"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}